Nitrous acid is a photochemical hydroxyl radical precursor in the atmospheric boundary layer that is formed on ground layer surfaces. Despite the importance of HONO in oxidative atmospheric chemistry, reactions of oxides of nitrogen that form HONO on environmental surfaces are among the most misunderstood processes. Contributing to this uncertainty is the fact that nitrogen oxides readily interconvert between a range of oxidation states via redox pathways often facilitated by soil organic matter and minerals such as Fe hydr(oxides). We present here the first survey of HONO formation on real soil samples collected from across the United States. Gas phase reactivity measurements were combined with chemical composition measurements on soil organic matter and mineralogy to identify the surface reactive sites responsible for abiotic HONO formation. Results provide insights not only into driving forces of reactive nitrogen transformation on ground level surfaces, but also on the role of metal organic matter interactions in aqueous aerosol and particulate matter.

Towards identifying the reactive sites responsible for nitrous acid formation on soil surfaces

2019 Fall National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.